This invention relates to a structural connector for attaching two structural members together in a structure such as a building, the structural connector having a two-tiered embossment formed in at least one of the members of the connector to strengthen the connector.
The structural connector of the present invention has particular application in the field of structural hangers where an elongated, generally horizontally disposed structural member is hung from a supporting structure, both being part of the structural frame of a building.
In light frame construction, it is common to hang the joists supporting the floors of the building from horizontally disposed members often called headers, beams or ledgers. The joists can be supported by hangers which are attached to the headers, beams or ledgers. One type of hanger used is called a top flange hanger. A top flange hanger has a portion or member that rests on the top surface of the supporting structure, increasing the strength of the connection.
Unfortunately, the presence of the top flange can interfere with the setting of the sub-flooring members on top of the joists and the headers and ledgers. The top flanges create an unevenness in the surface upon which the sub-flooring is installed.
Preferably, the flat top surfaces of the joists, headers and ledgers will all be uniformly level and set at the same elevation, once the members are set in place, although deviations are often made to allow for shrinkage of members made from wood or having wood sub-components. Also, preferably, the sub-flooring used is made up of large sheets of relatively thin planar material, such as plywood or oriented strand board, that can be laid down on the level top surfaces of the headers and ledgers resulting in a uniformly flat surface for laying down the flooring.
Thus, it is desirable to minimize the thickness of any members, such as fasteners, fastener heads or hanger components that will project above the level of the top surfaces of the ledges, headers and joists. When such members project above the ultimate top level of the structural members of the flooring, they create unevenness in the surface for the subflooring, commonly known as reveal problems.
Thus, when top flange hangers are used, it is desirable to make the material of the top flange as thin as possible. However, the top flange must still be strong enough to carry the desired loads imposed on the hanger. One means of strengthening the top flanges of hangers is to create embossments or deformations in the top flange hanger that extend into the back members of the hangers. The problem with typical strengthening deformations or embossments is that too much of the material of the top flange is deformed to too great a height, thus creating reveal problems.